/* LibTomCrypt, modular cryptographic library -- Tom St Denis
 *
 * LibTomCrypt is a library that provides various cryptographic
 * algorithms in a highly modular and flexible manner.
 *
 * The library is free for all purposes without any express
 * guarantee it works.
 */
#include "tomcrypt.h"

/**
  @file der_length_printable_string.c
  ASN.1 DER, get length of Printable STRING, Tom St Denis
*/

#ifdef LTC_DER

static const struct {
   int code, value;
} printable_table[] = {
{ ' ', 32 },
{ '\'', 39 },
{ '(', 40 },
{ ')', 41 },
{ '+', 43 },
{ ',', 44 },
{ '-', 45 },
{ '.', 46 },
{ '/', 47 },
{ '0', 48 },
{ '1', 49 },
{ '2', 50 },
{ '3', 51 },
{ '4', 52 },
{ '5', 53 },
{ '6', 54 },
{ '7', 55 },
{ '8', 56 },
{ '9', 57 },
{ ':', 58 },
{ '=', 61 },
{ '?', 63 },
{ 'A', 65 },
{ 'B', 66 },
{ 'C', 67 },
{ 'D', 68 },
{ 'E', 69 },
{ 'F', 70 },
{ 'G', 71 },
{ 'H', 72 },
{ 'I', 73 },
{ 'J', 74 },
{ 'K', 75 },
{ 'L', 76 },
{ 'M', 77 },
{ 'N', 78 },
{ 'O', 79 },
{ 'P', 80 },
{ 'Q', 81 },
{ 'R', 82 },
{ 'S', 83 },
{ 'T', 84 },
{ 'U', 85 },
{ 'V', 86 },
{ 'W', 87 },
{ 'X', 88 },
{ 'Y', 89 },
{ 'Z', 90 },
{ 'a', 97 },
{ 'b', 98 },
{ 'c', 99 },
{ 'd', 100 },
{ 'e', 101 },
{ 'f', 102 },
{ 'g', 103 },
{ 'h', 104 },
{ 'i', 105 },
{ 'j', 106 },
{ 'k', 107 },
{ 'l', 108 },
{ 'm', 109 },
{ 'n', 110 },
{ 'o', 111 },
{ 'p', 112 },
{ 'q', 113 },
{ 'r', 114 },
{ 's', 115 },
{ 't', 116 },
{ 'u', 117 },
{ 'v', 118 },
{ 'w', 119 },
{ 'x', 120 },
{ 'y', 121 },
{ 'z', 122 },
};

int der_printable_char_encode(int c)
{
   int x;
   for (x = 0; x < (int)(sizeof(printable_table)/sizeof(printable_table[0])); x++) {
       if (printable_table[x].code == c) {
          return printable_table[x].value;
       }
   }
   return -1;
}

int der_printable_value_decode(int v)
{
   int x;
   for (x = 0; x < (int)(sizeof(printable_table)/sizeof(printable_table[0])); x++) {
       if (printable_table[x].value == v) {
          return printable_table[x].code;
       }
   }
   return -1;
}

/**
  Gets length of DER encoding of Printable STRING
  @param octets   The values you want to encode
  @param noctets  The number of octets in the string to encode
  @param outlen   [out] The length of the DER encoding for the given string
  @return CRYPT_OK if successful
*/
int der_length_printable_string(const unsigned char *octets, unsigned long noctets, unsigned long *outlen)
{
   unsigned long x;

   LTC_ARGCHK(outlen != NULL);
   LTC_ARGCHK(octets != NULL);

   /* scan string for validity */
   for (x = 0; x < noctets; x++) {
       if (der_printable_char_encode(octets[x]) == -1) {
          return CRYPT_INVALID_ARG;
       }
   }

   if (noctets < 128) {
      /* 16 LL DD DD DD ... */
      *outlen = 2 + noctets;
   } else if (noctets < 256) {
      /* 16 81 LL DD DD DD ... */
      *outlen = 3 + noctets;
   } else if (noctets < 65536UL) {
      /* 16 82 LL LL DD DD DD ... */
      *outlen = 4 + noctets;
   } else if (noctets < 16777216UL) {
      /* 16 83 LL LL LL DD DD DD ... */
      *outlen = 5 + noctets;
   } else {
      return CRYPT_INVALID_ARG;
   }

   return CRYPT_OK;
}

#endif
